1. Field of the Invention
The present invention relates to a bulb socket terminal in an automotive lamp, and more particularly to a terminal having a structure which may be insert-molded in a socket body.
2. Description of the Relevant Art
Conventionally, a technique of insert-molding a terminal in a housing body of a connector is known, but a technique of insert-molding a bulb socket terminal in a bulb socket with a connector has not yet been established.
Japanese Utility Model Laid-open Publication No. 59-79990 discloses a connector bulb socket as shown in FIGS. 8 to 12. Referring to FIGS. 8 to 12, the bulb socket is constructed of a socket body A, a terminal C adapted to contact a filament end B.sub.1 of a bulb B, and a ground terminal D adapted to contact a ground end B.sub.2 of the bulb B. The socket body A, the terminal C and the ground terminal D are independently manufactured before both the terminals C and D are received through a bulb insert hole a and secured in said socket body A.
Referring to FIGS. 13A and 13B, if the terminal C to contact the filament end B.sub.1 is insert-molded in the socket body A, a metal mold E.sub.1 may be used for enclosing a contact portion b adapted to elastically contact the filament end B.sub.1. In this case, if resin is filled in a hatched area G (corresponding to the socket body A) alone to secure the terminal C, there will be no problem. However, the resin actually flows also into a hatched area H because there is no wall or the like for inhibiting intrusion of the resin. (Although another metal mold to be coupled with the metal mold E.sub.1 is actually provided on the opposite side of the metal mold E.sub.1 with respect to the hatched area G, such a metal mold is not shown for the simplicity of the drawing.) For the above-mentioned reason, an amount of elastic displacement of the contact portion b is restricted to cause insufficient electric contact with the filament B.sub.1. To prevent the intrusion of the resin into the hatched area H, it may be considered to form the contact portion b into an S-shaped contact portion c as shown in FIGS. 14A and 14B. However, there remains a problem such that the resin still flows into an area of the contact portion c as shown by the arrows through a necessary clearance between the terminal C and a metal mold E.sub.2 or a gap therebetween due to lack of uniformity in finished sizes of the terminal C.
In case of insert-molding the ground terminal D, it may be considered to enclose a contact portion d adapted to contact the ground end by means of a metal mold F as shown in FIGS. 15A and 15B. However, the resin will flow into not only the hatched area G but also a hatched area J for the same reason as the above. As a result, the contact portion d is secured by the resin molded in said hatched area J, thus causing a problem that the bulb cannot be inserted.